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Graphene manufactured by the existing method (e.g., chemical oxidation) has limitations in application due to various disadvantages. Functionalized graphic nanoplates manufactured by mechanochemical reactions can solve physical and chemical defects. So, butadiene graphitic nanoplatelets (BDGNs) are first synthesized with solid graphite and butadiene gas by using a mechanochemical reaction. The product BDGNs have outstanding properties, including very good dispersion in common organic solvents (i.e., toluene), and can be used as a reinforcing filler for poly(styrene‐co‐butadiene) (PSB) because of their chemical affinity to butadiene units. BDGN/PSB_X (BDGN loading [X] = 0.2, 0.5, 1, or 2 wt.%) nanocomposites are readily prepared using a solution process. In result, the tensile strength and Young's modulus of the BDGN/PSB_0.5 nanocomposites increased by approximately 27.9% and 81.4%, respectively, compared with those of pure PSB. Because of the efficient load transfer from the PSB to the BDGNs through the good distribution and affinity of the BDGNs in the PSB, as well as the physical cross‐linking points of the BDGNs. Therefore, a mechanochemical reaction can form in situ a variety of graphitic nanoplatelets (GnPs) without additional reaction as a filler that has remarkable affinity with various polymers, including copolymers. [ABSTRACT FROM AUTHOR]

In order to improve the thermal and mechanical properties of poly(styrene-co-butadiene) (SBR) to use it as a pervaporation membrane in the separation of the azeotropic mixture toluene/methanol, poly(styrene-co-butadiene) crosslinked Maghnia-organo-montmonrillonite (CSBR/OMMT), a nanocomposite of different compositions was first prepared by a solvent casting method. SBR was crosslinked in situ in the presence of OMMT nanoparticles by an efficient vulcanization technique using sulfur as a crosslinking agent and zinc diethyldithiocarbamate as a catalyst. The structure and morphology of the hybrid materials obtained were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscope analysis. The thermal properties of these hybrid materials were studied by differential scanning calorimetry and thermogravimetric analysis/thermal differential analysis. The mechanical properties were studied by strength measurements. The results obtained occurred when the OMMT was incorporated in the CSBR matrix; a significant increase in the glass transition temperature of the SBR was observed which passed from −27 °C for virgin SBR to −21.5 °C for that containing 12 wt% of OMMT. The addition of OMMT nanoparticles to CSBR also improved the mechanical properties of this copolymer. When the OMMT content in the CSBR varied from 0 to 15% by weight, the tensile strength, the elongation at the nose and the modulus at 100% elongation increased from 3.45 to 6.25 MPa, from 162, 17 to 347.20% and 1.75 to 3.0 MPa, respectively. The results of pervaporation revealed that when the OMMT content varied between 3% and 12%, a significant increase in the total flux, the separation factor and the separation index by pervaporation increased from 260.67 to g m−2 h−1, 0.31 to 1.43, and 0.47 to 113.81 g m−2 h−1, respectively.

Experiments were performed to identify the reactive intermediate(s) involved in the degradation of several vinyl polymers upon exposure to chlorinated water. The potential intermediates of concern are Cl2, HClO, and singlet molecular oxygen, O2(a1Δg), all of which exist in chlorinated water and whose concentration profiles are pH-dependent. The degradation of polystyrene and poly(styrene-co-butadiene) films was monitored in a variety of pH-dependent experiments using FTIR spectroscopy. Data obtained indicate that Cl2 is the principle reactive intermediate that initiates polymer degradation, and that singlet oxygen does not play a significant role under these conditions. Moreover, poly(styrene-co-butadiene) samples were significantly more susceptible to the effects of chlorinated water than were polystyrene samples and, thus, identify olefinic residues as an important reactive functional group under these conditions. Data obtained also indicate that the thermal history of the sample is important. Specifically, upon immersion in chlorinated water, samples that had been exposed to high temperatures during processing and/or that had been annealed for longer periods of time degraded at a much faster rate than did samples that had only minimal exposure to high temperatures. This effect was particularly pronounced with the poly(styrene-co-butadiene) samples. These results are important with respect to the development of polymers that can better resist exposure to water that has been chlorinated to kill bacteria (e.g., drinking water). [Copyright &y& Elsevier]

In order to improve the thermal and mechanical properties of poly(styrene-co-butadiene) (SBR) to use it as a pervaporation membrane in the separation of the azeotropic mixture toluene/methanol, poly(styrene-co-butadiene) crosslinked Maghnia-organo-montmonrillonite (CSBR/OMMT), a nanocomposite of different compositions was first prepared by a solvent casting method. SBR was crosslinked in situ in the presence of OMMT nanoparticles by an efficient vulcanization technique using sulfur as a crosslinking agent and zinc diethyldithiocarbamate as a catalyst. The structure and morphology of the hybrid materials obtained were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscope analysis. The thermal properties of these hybrid materials were studied by differential scanning calorimetry and thermogravimetric analysis/thermal differential analysis. The mechanical properties were studied by strength measurements. The results obtained occurred when the OMMT was incorporated in the CSBR matrix; a significant increase in the glass transition temperature of the SBR was observed which passed from −27 °C for virgin SBR to −21.5 °C for that containing 12 wt% of OMMT. The addition of OMMT nanoparticles to CSBR also improved the mechanical properties of this copolymer. When the OMMT content in the CSBR varied from 0 to 15% by weight, the tensile strength, the elongation at the nose and the modulus at 100% elongation increased from 3.45 to 6.25 MPa, from 162, 17 to 347.20% and 1.75 to 3.0 MPa, respectively. The results of pervaporation revealed that when the OMMT content varied between 3% and 12%, a significant increase in the total flux, the separation factor and the separation index by pervaporation increased from 260.67 to g m−2 h−1, 0.31 to 1.43, and 0.47 to 113.81 g m−2 h−1, respectively. [ABSTRACT FROM AUTHOR]